A Nibble of Chocolate, Part Three

We North Americans are chronically concerned with our bulging stores of fat, which even exercise just does not seem to lessen at times. But there is hope - in the form of a chocolate bar of all things. This bar's key ingredient is cocoa, for it is cocoa that helps to burn the fat out of our fat cells. The inventor of this gopher technology kept cocoa butter out of his bar because it may add to our fat.

It all started when Dr. Lawrence CH Wang, Professor of Zoology at the University of Alberta, studied ground squirrels to learn how they burned their fat during hibernation as a way to stay alive and keep warm during the cold winter months. From the lessons they taught him, he invented a special type of chocolate bar that replicated in humans the squirrels' fat-burning mechanisms. One of the vital ingredients in that bar is cocoa.

To backtrack a bit, you need to know that there is a group of closely related chemical compounds found naturally in plants, which include caffeine, theobromine, and theophylline. These are called "xanthines," and cocoa contains two of these compounds. Of the many effects that xanthines have on the human body, the one that's really cool is the one that aids fat burning. But before we explore how xanthines help to burn fat, let's first look at why it is so difficult to use the fat stored in our bodies while exercising unlike when resting, when we burn about 50 percent carbohydrates and 50 percent fat.

Our human body evolved to help us survive in the wild. But now that we North Americans live in the luxury of urban life, sometimes these parts -- even small chemical messengers -- can get in the way of good health. One of these parts is a chemical that prevents our body from using fat as fuel. Dr. Wang decided to focus his research on how this chemical, adenosine, a byproduct of our metabolism, uses and moves the fat out of our fat cells in the form of free fatty acids or rather blocks their release. It seems rather perverse for evolution to create adenosine as a way to block the burning of fat, but it evolved in order to protect our ancestors from starving to death during times of famine.

Adenosine protected our ancestors by storing and conserving fat, a potent energy source. Since finding plentiful food in the wild is both dangerous and difficult, conserving any surplus energy in the fat cells helped our species survive. During brutal famines, humans could then live off of their fat. But that need no longer exists for us fat westerners. Instead of starvation, we now worry about our growing energy stores and how to get at that stored energy, particularly while exercising.

At rest using fat is not too much of a problem because adenosine exists in low concentrations while doing things like lying on the couch, watching TV. While resting, we burn as much fat as carbohydrates. But when we start exercising, adenosine's concentrations soar so that it almost completely prevents our bodies from gaining access to all that plentiful stored energy.

Meanwhile, a neurotransmitter (the chemical messenger of a nerve cell) called "norepinephrine" tries to release that fat. It does this by activating adenylate cyclase, an enzyme bound into the fat cell membrane, which then releases fatty acids from the fat cells into the bloodstream, where they become free fatty acids, free to be used as fuel by other cells like those in our muscles.

Unfortunately adenosine is more powerful than norepinephrine and works against it. It also ups the ante by inhibiting the enzyme adenylate cyclase, preventing the freeing of those fatty acids. Basically, during exercise, adenosine kicks into high gear to conserve those fatty acids. And then within a minute of being formed and exerting this negative effect on fat release, adenosine is broken down. Since the muscles still need energy to work hard, the body switches to carbohydrates as its prime source of fuel.

Dr. Wang studied this fat-conservation process for 15 years. He postulated that if one can block the adenosine receptors, then the effect of adenosine - namely preventing fat from being moved and used - would be blocked. He found the answer in xanthines.

According to Dr. Wang, naturally occurring xanthines in food act at fairly low concentrations to block the effect of adenosine. They do so by locking into adenosine receptors before adenosine has a chance to. (A molecule can only exert its effect by joining with its receptor, like two pieces of a jigsaw puzzle.) And so adenosine cannot act against norepinephrine, and it cannot prevent those fatty acids from being released into the bloodstream before it is broken down.

During exercise, muscles use a few free fatty acids and mostly glucose for fuel because of that bad guy adenosine. We get that glucose from carbohydrates, which is why athletes like to "carboload" their bodies before exercising or competing. The energy bars found in health food stores and exercise-related stores provide carbohydrates on the run, preventing the need for that ubiquitous large spaghetti dinner. But as Dr. Wang likes to say, "using carbohydrates as fuel is like burning coal": the byproducts include carbon dioxide and water and that nasty lactic acid even under optimal aerobic conditions. Lactic acid causes fatigue and stiff muscles.

In contrast, fat is a clean fuel, like natural gas; its only byproducts are carbon dioxide and water. No lactic acid. And so the less carbohydrates you use for fuel and the more fat instead, the less lactic acid is formed, the longer you can sustain exercise, and the better you will feel afterwards. No to little of that post-exercise fatigue and stiffness. But how to do this?

Knowing xanthines provided the key to stopping adenosine, and chocolate contained two of them, Dr. Wang looked for a source and discovered cocoa was it. And not just any cocoa, but the right one. Dr. Wang tested 30 different types of cocoa from all over the world to find one that exerted a functional effect -- that adenosine-blocking effect-- without causing undesirable side-effects. The cocoa he chose is a trade secret. I couldn't pry it out of him.

He put that cocoa into a chocolate bar and created a functional food that switches the body to an alternative fuel: fat. He calls it a functional food because it uses ordinary food ingredients in combination to exert a physiological effect. Called the "Access Bar," it provides 154 calories in proteins, fats, and carbohydrates in a patented formula that assists in the liberation and burning of fatty acids during exercise. Unlike the usual energy bar, this bar does not contain sufficient calories to act as a fuel source while exercising, although the slow release of its ingredients contribute partly to the feeling of fullness after eating it. Instead, it works by blocking the action of adenosine and by supplying just enough glucose to burn the free fatty acids - without producing lactic acid or causing coffee-type stimulation. No hyper drive; just smooth drive.

If you eat the bar on an empty stomach and do not exercise, a feeling of fullness will last for about 3 to 4 hours, but it will not burn fat as effectively. You will however be able to withstand the brutal cold of a Canadian winter much better during those hours (remember, it's gopher tech).

As Dr. Wang pointed out, one cannot get the same effect from eating a slice of chocolate cake with a glass of milk because "it's how (the ingredients) are put together that makes the difference." And, as well, what sets this bar apart from others is (1) it is scientifically researched and substantiated by over 30 papers published in international journals; (2) it is scientifically innovative and the government of Canada and the University of Alberta hold a patent on it in Canada, the US, and Europe; and (3) it is scientifically predictable, that is, if you eat the bar according to the instructions on the label (15 minutes before exercising on an empty stomach with a glass of water), you will always feel the difference, even the very first time you use it. I certainly did when I walked along the Rideau Canal on a bright, freezing winter day for 2 hours, yet remained toasty warm. I couldn't skate that day but wanted to enjoy this Ottawan pleasure anyway.

So does the Access Bar* work? Dr. Harvey Anderson, Professor of Nutrition at the University of Toronto, cautions that it is easy to make claims based on logic, but one needs scientific studies with the actual product to prove that it is effective. The question to ask is, "is the dosage of the active ingredients sufficient to make a response?"And so I did.

In a series of double-blind randomized studies, Dr. Wang tested the effectiveness of first a liquid formula and then the Access Bar versus placebos in improving the cold tolerance of volunteers exercising moderately or strenuously in a room cooled to -10 degree Celsius, with a light wind simulated. The volunteers were dressed in shorts (men) or shorts and a t-shirt (women). Eating the Access Bar enhanced the volunteers' cold tolerance; being able to tolerate cold better relies on being able to sustain aerobic activity -- shivering and exercise -- the kind that doesn't produce lactic acid. This study proved that the Access Bar enhanced sustained aerobic activity.

And then there's the anecdotal evidence, not as strong as scientific double-blind trials, but more interesting. Those who've tried it wax enthusiastic about it. They believe wholeheartedly in its effectiveness. As long as they follow the instructions, they notice a huge difference both during and after exercise. They have more energy to keep on exercising and even afterwards. Best: they have little to no stiffness the next day.

One should always be wary of anecdotal evidence, however. Sometimes things work because we expect them to (the placebo effect). Sometimes they work, and we don't know why. And sometimes they don't work, but we never hear about the failures. But the scientific evidence supporting the effectiveness of this functional food - food that has a physiological effect - is convincing.

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*Melaleuca Inc. has the exclusive right to manufacture and distribute Dr. Wang's chocolate bar, the Access Bar in North America. It is available in Canada as the Access Bar from Melaleuca of Canada, Inc.

Cocoa contains the xanthines caffeine and theobromine. Although cocoa contains little caffeine, its theobromine content is high enough to account for cocoa's caffeine-like effects. The human body synthesizes theophylline from caffeine.

Caffeine

Athletes consume caffeine to boost their physical and mental energy and endurance. The problem though is that they can also get a faster heart rate, higher blood pressure, digestive upset, shakiness, and tremors. The shakiness can be a particular problem to those athletes who need steady hands, like biathletes.

How effective the caffeine is in boosting an athlete's performance without causing unwanted side effects depends on its quality. This is why Dr. Wang tested so many different cocoas. Because of its stimulatory effect on performance, the IOC has declared caffeine a banned drug for athletes competing in the Olympics.

Theobromine

Theobromine, though, does not have the exact same intensity of effects on the human body as caffeine does. This is important in the development of any new food product using a xanthine-containing ingredient: the differences in the intensity of effects will lead to choosing one xanthine over another to achieve the desired result while causing fewer side effects. And so although many other foods, like tea, coffee, and some South American fruits, contain xanthines, cocoa has the right combination to produce the desired result of fat burning without those dreaded caffeine shakes. Chocolate rules!

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